80 



Fishery Bulletin 91(1), 1993 



mens. There are 27-29 myo- 

 meres. 



The gut is a convoluted tube 

 in our smallest specimen 

 (2.8mm). It quickly thickens, 

 coils, and becomes triangular by 

 4.4 mm. The anus begins to mi- 

 grate by 3.9 mm and is in the 

 adult location (between the pel- 

 vic fins) by 4.9mm (Fig. 3C,D). A 

 light organ that surrounds the 

 anus first appears in 3.6 mm lar- 

 vae and is well developed, rugose 

 in appearance, and heavily pig- 

 mented by 4.4 mm. Ventral stri- 

 ated tissue, characteristic of 

 adults, is present in the 7.9 mm 

 specimen. 



Insufficient specimens were 

 available to fully document 

 flexion; however, flexion was just 

 about to commence in a 4.9 mm 

 specimen, was well underway in 

 a 5.7 mm specimen, and had been 

 completed in a 7.9 mm specimen. 



Fin development Development 

 of the pelvic fins is precocious. 

 Even our smallest specimen has 

 a full pelvic complement of 7 ele- 

 ments (although ossification is 

 not completed until 4.4 mm). The 

 pelvic fins are large, up to 35% 

 body length at 4.9 mm, and reach 

 beyond the anal-fin origin in all 

 specimens. The limited number 

 of specimens precluded docu- 

 menting initial dorsal- and anal- 

 fin anlagen development; how- 

 ever, the separation from the 

 body of the posteriormost anal 

 base in our 4.1 mm specimen sug- 

 gests a finfold development simi- 

 lar to Paratrachichthys. Both dor- 

 sal and anal bases are present 

 by 3.94.1mm, and incipient rays 

 appear above these bases by 

 4.4 mm. Incipient rays appear in 

 the pectoral fin shortly thereaf- 

 ter (4.9 mm). Ossification of the 

 dorsal, anal, and pectoral fins 

 commences in flexion-stage lar- 

 vae, with a full complement in 

 all fins present by 7.9 mm. 



Figure 2 



Development stages of Paratrachichthys sp.: (A) 3.9mm, (B) 4.3mm, (C) 4.7mm, (D) 

 5.5 mm, (E) 7.8 mm. Arrows indicate location of anus. 



